1. Field of the Invention
The present invention relates to an apparatus for improving uniformity used in a backlight module and, more particularly, to an apparatus that provides improved illumination uniformity for a liquid crystal display (LCD) or a liquid crystal TV.
2. Description of Related Art
Currently, there are two types of lighting module for a flat panel display. One is the back type, and the other is the front type. The backlight module is further classified as a side-light (edge-light) type and a directly-under-light (bottom light) type according to their locations of light sources. The directly-under-light backlight module is mostly used in a stationary product, such as a desktop LCD or an LC TV as it has a heavy appearance. Because the light source of a directly-under-light backlight module is located right under the displaying area, the profile of the light sources easily causes a non-uniformity of brightness, shadows, or line defects to the displaying image. Generally, a light-diffusing sheet is used to uniformly diffuse the illuminating light so that the shadows or line defects are blurred. Additionally, some light diffusing sheets are mounted with micro particles having various sizes and densities for refracting or diffusing the illuminating light as uniformly as possible. However, the illuminating light will be absorbed when passing through the light-diffusing sheet and  only about 50% of the original is remains, which leads to a low efficiency of light utility rate.
Therefore, it is desirable to provide an improved an apparatus for improving uniformity used in a backlight module to mitigate and/or obviate the aforementioned problems.